It Finally Happened: 5 Axis CNC for the DIY and Maker

If you’d asked me up until very recently whether 5 axis was practical for the CNC DIY’ers and Makers, I would’ve said “No!” without hesitation. Not only is the hardware complex, but 5 Axis CAM was expensive. Much of this has now changed fairly recently. Yes, the hardware is complex and most 5 Axis CAM is still expensive, but there are an increasing number of proof points that is is possible to have a go at 5 axis CNC for the hobbyist. Let’s have a look at recent developments in this area, but first:

Why Would You Want 5 Axis?

Given that 5 Axis is not at all easy or common, even for Pros, why would a hobbyist want 5 axis? Sure, there’s always the desire to push the envelope, to do something the mainstream hasn’t done yet. That’s primal Maker juice at its best, and we’ll trot out this popular 5-axis video just to get those juices flowing:

How can you not love this cool 5-axis vid? Gimme, gimme, gimme!

But there are sound practical reasons to want to do 5 Axis as well. We’ve written about the advantages of 5 Axis CNC before, but a quick recap here is in order. Here are the most important bits:

– Better Surface Finish = Less Manual Cleanup Work: By tilting the workpiece just right, the optimal engagement between cutter and material is obtained. The result is a far better surface finish, especially on complex 3D curves.

– Fewer Setups: When you can get at nearly every face of the part except for the very bottom, you have fewer setups needed. This is especially helpful for the hobbyist who may only be trying to make a one-off part. No need for complex fixturing and lots of setups with 5 axis giving the cutter better access.

– Better Accuracy: Every time you change a setup, a little error will creep in. With fewer setups, or perhaps even just 1 setup, this source of error is eliminated.

– Machine Parts Not Otherwise Possible: Let’s face it: something like the helmet shown in the video wouldn’t even be possible without 5 Axis CNC. Many parts that require a lot of undercutting will be much more difficult without 5 Axis CNC. It isn’t even just a question of something curvy like the helmet. With 5-axis, a part can be tilted to allow a shorter tool to get down in a pocket, thus allowing for more rigidity and less tendency for the tool to deflect and chatter. On a lightweight hobby machine, any increase in rigidity is welcome.

OK, now you’re sold, so what can you do about it? It’s not going to be easy, but as I said, there have been a few developments worth checking out:

Pocket NC: Slick Kickstarter Desktop 5-Axis Mill

Many of you will have heard of the Pocket NC, a truly slick 5-Axis CNC Mill:

Pocket NC 5-Axis Desktop Mill…

With linear rails, a sweet high speed spindle, and trunion table, the Pocket NC looks the part. It’s even set up as a horizontal mill, which no doubt gives it greater rigidity than might otherwise be the case. 280 backers pledged $355,833 on Kickstarter to help bring this project to life. The Kickstarter closed just a couple of weeks ago, so it’s way too early to tell much, but this mill looks extremely promising. Early signs are good as the Kickstarter sold out 3 weeks early and this enabled them to get a head start making parts for the machines:

Parts to assemble Pocket NC’s are stacking up…

With two machinists, a mechanical engineer, and a software guy, it’s no wonder the machine looks so good. Their attention to detail really shows. Here’s a shot of the machine in action machining what turns out to be a gorgeous little aluminum engine block:

As mentioned, the Kickstarter sold out. We’ll have to wait until they’ve delivered all the machines to that crowd to see whether there will be a Pocket NC for the rest of us, as well as what the reaction of the first group of owners may be. Personally, I’m hoping everyone loves the machine and that it will be available at their target price of $3500. That would be quite an accomplishment to be able to purchase a high quality 5 axis desktop CNC mill at such a price.

There have been other desktop 5 axis machines shown, even some on Kickstarter, but the Pocket NC is the first one that seemed so polished. These things are a bit like the 4 minute mile. Until someone actually ran a 4 minute mile, it seemed impossible. Once it had happened, quite a few managed to run it not long after.

Affordable 5-Axis CAM

The main reason I would have said “No” to 5-Axis for hobbyists up until recently was not hardware, it was software. Talented hobbyists have been modifying a 4th axis to turn it into a 4 axis trunion table for quite some time. Here is one such:

Shopmade 5-Axis Mini-mill…

Building a 5-axis mill is hard enough, but programming it is nearly impossible without CAM, and until recently, 5-axis CAM was very expensive. Before the advent of true 5-axis CAM, about the best that was available were toolkits to help simplify the hand programming, such as CNC-Toolkit. While extremely useful, such software was still too hard for most people to tackle. Just visualizing true 5-axis tool paths is nearly impossible for most.

But, a lot is changing. Autodesk is rocking the boat particularly hard for the CAM world with its Fusion 360 software. It’s available cheap or even free for hobbyists, and comes with a potent integrated CAD (which of course Autodesk is famous for) and HSMWorks CAM. I really like the HSMWorks package–it’s a first class, easier to use, pro-quality, clean-sheet-of-paper package. And while there’ve been some usability and stability issues in Fusion 360, Autodesk is pushing hard to improve it, and the price is certainly right for the hobby market.

The Fusion 360 Ultimate version includes full simultaneous 5-axis CAM, and is actually approachable for the Hobby-level market for the first time. Here is a video of the PocketNC showing how they did a duck call in 5-axes:

5-Axis from CAM to Finished Part…

Conclusion

It’s premature yet to declare that DIY 5-Axis is here for the masses, but I don’t think it’s premature to suggest that it isn’t far away or that it is almost within reach. Talented hobbyists can get there today, thanks to the availability of suitable software. The rest who want to be able to buy an off-the-shelf machine that’s ready to make parts will have to wait a little while longer.

The future is bright. When I first started playing with CNC years ago I used to think it was amazing that a person could own one of these machines. After all–they helped put men on the moon. Now there are more an more of them out there. I have been meeting people accidentally for a while now that are deeply involved, which is a sign of how commonplace it is becoming. The thing is, we ain’t seen nothing yet, as the saying goes. Much more to come!

If you’re a hobbyist with a 5 axis CNC, share your experiences in the comments with us. I’m sure our readership would love to hear from you.

Just a small nit to pick, but Fusion does not currently do simultaneous 5-axis machining. It does 3 axis simultaneous with indexing on the 4th and 5th axes. True 5-axis is not scheduled to be included until next year some time.

5 Axis CNC appears to be no big deal. The hardware is cheap these days. The value and cost is in the software and the knowledge to effectively use it.

Here is my current situation as a hobbyist:

When I retrofired an imported mini mill back in the 90s, the biggest consideration was torque per dollar. $800 for 3 125 oz inch steppers and driver from MAX-NC. I recently purchased 4 1800 oz-in steppers, drivers, and power supplies and 5 each 560 oz-inch steppers, drivers, breakout board and pendant all for about $800, shipping from China included. The actual major cost consideration is overseas shipping cost. The 560 oz-inch stepper system was a small marginal cost.

The 1800 oz-in steppers are for my large Taiwan Mill and a Plasma cutting table yet to be built. The 560 oz-in steppers will be used for a mini mill and 9X27 lathe.

Swapping steppers between machines is not an issue. I could have purchased more of the small steppers but then the shipping costs would have increased greatly. I have the electronics mounted in a roll around cabinet so it can travel between different machines. (Can not post picture here)

My intention with the 5 small steppers is to have X,Y,Z, with a rotary table and trundle on the milling machines. I have no plans to mill turbine blades, but the rotary table is necessary for gears, and as for the trundle, I guess that is something I will eventually find a use for. The lathe will be redesigned from the bed and spindle up. Maybe the carriage will be reused but there will be a turret for tool changes on the carriage.

It is Summer right now and am building a shed to make room for the Plasma cutting table. CNC work is on hold until the snow starts falling.

The biggest hurdle is finding a computer and software to run everything. I was going to go with Mach3 and a motion control board but the price skyrockets once 5 and 6 axis are implemented. I am comfortable with LinuxCNC but finding a computer for it is a bother and the dependence on the obsolete parallel port is a nagging problem.

The Home Made 5 Axis Video here pointed me to TurboCNC which is 8 Axis. I can work with DOS and the $50 price tag is nice. I found it difficult to get one of my old computers and a License for MS-Dos to work together. There is Free-Dos which may work.

Maybe by the time winter sets in and I start working on the CNC system again, the Maker Community will have a usable Motion Control board running off an Arduino or Raspberry Pi.

It appears that there are motion control boards for LinuxCNC. I assume Tormach built their own along with their own modification of LinuxCNC Code. The Last I read on LinuxCNC was that they were still very committed to the parallel port with no intention of supporting other interface options. It there a motion control board for LinuxCNC that will handle more than 4 Axis?

John, LinuxCNC supports quite a few motion control boards. Tormach supports the Mesa board, which is one of the most popular. I really like LinuxCNC and it’ll be my first choice for any DIY project from here on out.